snmp traps, not all gets an event

[Finn Aksel Falkenberg]

I'm running HP Sim 5 on linux rh es 4.0. I have hooked up around 100 linux klients running linux rh es 3.0 - and it all works well. I get both healt and snmp traps sent.

The sim server is running through a firewall and are beeing NAT'ed.

But, after adding some new servers my sim-server wont put snmptraps from these new one's in the event view.

From tcpdump I can see that the trap does not stop in the firewall. From tcpdump:
snmptraps from this works:
--
15:30:21.102112 IP 172.27.52.13.32925 > 172.27.48.191.snmptrap: C=manager Trap(38) .1.3.6.1.4.1.232 172.27.52.13 enterpriseSpecific s=11003 537323800 .1.3.6.1.2=[|snmp]
--
snmptraps from this, does not work
--
15:11:13.953838 IP 172.27.52.90.32840 > 172.27.48.191.snmptrap: C=manager Trap(38) .1.3.6.1.4.1.232 172.27.51.90 enterpriseSpecific s=11003 898498366 .1.3.6.1.2=[|snmp]
--
(I use hpasm to send test snmptraps)

Is there some way I can debug what happens when my new server sends the snmptrap? Can I make the SIM server accept all snmptraps and tag them as uknown?

Are there other things I should have a look at regarding these kind of problems?

[Finn Aksel Falkenberg]

I have found out a bit more. The servers that sending snmptraps does not work for has got two network interfaces.

Default gateway is out eth0, I want to send snmptraps out eth1. To get this to work without routing on the host, I have NAT'ed the hp sim through the firewall.

If I disable eth0 the snmptrap comes through to the sim, so there is some network issues. But I'm not sure how to debug this - my knowledge of sim and snmp is not good enough.

I'll appriciate any hints and tips.